There is a magnificent large lake in the highlands of the Caucasus. It is located at an altitude of 1900 meters above sea level. The lake is called like this: Sevan. Armenia is the country on whose territory it is located.
It is the lake that is the habitat of a fish called the Sevan trout. By the way, it is highly valued by fishermen. In addition to Lake Sevan, the trout, the photo of which is presented in the article, is also found in nearby rivers.
Description
Let's talk more about this fish. What does she represent? Sevan is a special kind of trout. Its name comes from the Latin salmo ischchan. In Armenian, the word ishkhan means "king". So she was named for her beauty and grandeur compared to other fish. After all, some of its individuals can reach a weight of up to seventeen kilograms. Sometimes there is a Sevan trout, the body length of which is one meter. As you can see, a real giant! Back in the fifteenth century, this fish was taken to various countries of the East.
Scientists also divide the Sevan trout, the photo of which is in the article, into four species, or, in other words, races. Moreover, they all differ fromEuropean trout.
Winter Ishkhan
So, one of the species of this trout is called winter ishkhan. Sometimes it is also called winter bakhtak. This type of trout is the largest. There were cases when the caught individual was seventeen kilograms, and its length was 104 centimeters. Impressive size! Then, when the winter ishkhan is feeding, its color is silver-white, and the back has a steel-colored color. He has few dark spots, and they are surrounded by a rim along the edge, of a light color. At the same time, they are never x-shaped, when compared with brown trout. The food of the winter ishkhan is amphipods, whose habitat is the bottom of the reservoir.
The maturation age of this type of trout is four or five years. At a time when spawning begins in fish, males change color. They darken significantly, and their fins become almost completely black. They have a few red spots on their sides, and the light rims on the rest of the spots stand out quite clearly. The females remain unchanged. Spawning occurs directly in the lake itself. The number of eggs can reach four thousand. Before the lake level dropped, two stocks of fish were isolated: one spawned from October to January, and the other from January to March. In this case, spawning took place at different depths. For the first, the depth was 0.5-4 meters, and for the second - 0.5-20 meters.
Winter bakhtak is especially appreciated by fishermen. It used to be an important fishing target. However, after the level of Sevan fell, many trout spawning places remained on the shore. Therefore, now this type of fishquite rare.
Summer Ishkhan
The second type of Sevan trout is the summer ishkhan. This fish is also called summer bakhtak. It was named so because it lays eggs in spring or summer. Its spawning takes place in the Bakhtak-chai and Gedak-bulakh rivers, as well as in Sevan itself, in the pre-estuary sections of the lake. This type of trout is smaller. Its weight, if you take the maximum, reaches two kilograms, and its length is about 60 centimeters. Summer ishkhan ripens at the age of 2-7 years. This type is a less prolific type of trout.
Such a fish can spawn a little more than a thousand eggs. Often, red spots can be seen on the sides of the summer bakhtak fish. The commercial stock of this species is declining every year due to the fact that the path to the spawning place was practically blocked.
Bojack
Another subspecies of the Sevan trout is the bodjak. This is a dwarf type of trout, and its size is quite small. It is known that the largest individual caught did not reach a length of thirty centimeters. And their average length ranges from 24 to 26 cm. Usually, males of the bojack often have red spots on the sides.
Spawning in this species of trout occurs only in Lake Sevan (Armenia). After reaching the age of three or four years, it begins to spawn. It should be said that at the same time she does not build nests to lay eggs, but throws them all over the bottom of Sevan. Bojack spawns from October to November. Moreover, scientists previously believed that this process occurs at a depth of about fifteen meters,but after the drying of the coastal zones, spawning grounds of bojak were found at a depth of forty meters. However, their area is rather small and cannot renew the lost coastal areas, and therefore the number of this fish has declined sharply.
Gegharkuni
Well, the last subspecies of the Sevan trout is called gegharkuni. Its young resemble the parr of other salmon. Their coloring has a slightly different shape than other types of trout in Sevan. Gegharkuni has dark transverse stripes and brown-yellow and red spots on the body. Their feeding takes place after a year of stay in the lake. Their colors are darker than those of ishkhan, but the shade is also silver.
Its food is not only benthos, but also zooplankton, located mainly in the water column and moving with the flow. This is what distinguishes gegarkuni from other types of trout. It spawns only exclusively in running water, that is, in rivers.
Sevan trout: numbers
Even in the 20s of the last century, they began to produce artificial breeding of summer ishkhan and gegharkuni. Until the mid-forties, the commercial stock was estimated at 1.6 million individuals. However, further on, the living conditions in the rivers of young animals deteriorated significantly, and the path to spawning was actually blocked. In view of this, after the fifties, gegharkuni and summer ishkhan began to be bred only at fish hatcheries.
Despite all the measures taken to preserve the number of Sevan trout, the collection of caviar at fish hatcheries has decreased. All these conditions, including the lowering of the water level, andthe reduction of natural spawning grounds for fish led to the fact that the number of all species began to decline sharply.
Eutrophication has made a significant contribution to all this. Eutrophication is an increase in the primary productivity of waters due to an increase in nutrients in them, such as mainly fluorine and nitrogen. These components can be introduced into water bodies through industrial and municipal effluents, after washing off from fertilizer fields or with precipitation, for example. At first, this may be beneficial for the fish, as there is more food. However, after all this, the quality of the water deteriorates. The coastal zone begins to overgrow, the water becomes cloudy, the transparency becomes less, and, accordingly, the level of oxygen also decreases.
Critically Endangered Species
In a particularly difficult situation, due to changes that occur in the lake itself and other water bodies, the largest and smallest species of trout, bodzhak and winter ishkhan, turned out to be. This fish spawns in the lake itself. These species are in danger of extinction. And so the fish called the Sevan trout was declared protected and listed in the Red Book.
